Ventilated parachute



May 28, 1929.

o. A. BAKER VENTILATED PARACHUTE Filed July 15, 1927 m. hms.

U WELL B KE Invent 0r J Hftorng Patented May 28, 1929.

UNITED STATE OSWELL A. BAKER, 0F MON'IEREY PARK, CALIFORNIA.

Application filed July 13,

My invention pertains to parachutes of a novel type wherein ventilation or circulation of air through the envelope is provided.

Among the objects sought by me in this invention are the following: to provide a parachute, the envelope of which will maintain a relatively horizontal plane; to reduce the area over that of the ordinary type to bear a like load; to eliminate in great measure the danger of collapse of the envelope; to insure positive and quick opening of the envelope; to increase stability and eliminate drift; to provide streams of rapidly moving air as a lifting force on the under side of the envelope; to create a partial vacuum above the envelope as additional lifting force.

I attain these objects b the provision, formation and assemblage 0 members and parts illustrated in the accompanying drawings, in which Figure 1 is a schematic drawing of my invention, showing three identical units compounded to form a multiple leaf parachute, the various leaves diifering only in diameter.

Figure 2 is a view of the top of my single leaf parachute, in the direction of the arrow in Figure 1.

Figure 3 is a schematic cross-sectional drawing of my single leaf parachute, showing the proximate lane of the same when in the air and sustaming a load.

It is an established fact, (U. S. Bureau of Standards), that an open or touring type of automobile olfers more air resistance than a closed car, all other factors being equal. In designing my invention I have therefore held in mind the belief that properly controlled circulation of air below a parachute would add greatly to its buoyancy.

In the ordinary type of parachute the air within the cupped envelope is dead air and useless, and in my opinion the sustaining or lifting surface is only equivalent to the area of the opening, (with possibly some overhang of the envelope). Furthermore, I hold that the said dead air is but a cushion for the free air below, and forms a convex surface below the mouth of the parachute which sheds the live air laterally in all directions. In other words, the efliciency of the ordinary parachute is not in direct ratio with the area of the envelope, but actually depends VENTILATED PARACHUTE.

1927. Serial No. 205,368.

on the amount of surface presented to the free air below by the convex cushion of dead air.

Furthermore, it would appear that the dead air contained in the ordinary type of parachute is somewhat heavier than the surrounding free air, owing to pressure from below through the mouth, and is therefore a handicap to liftin power rather than an aid. My invention see lrs to overcome the above mentioned objections to common practice in design of parachutes by providing'for full lifting power (or air resistance) throughout the entire surface area of the envelope, augmented by rapid circulation of live air from all sides through an aperture in the top of the envelope.

Referring more particularly to the draw mgs:

1 indicates the envelope of a parachute.

2 indicates a smaller parachute envelope in a multiple leaf parachute.

3 indicates a smaller parachute leaf than 2, in a multiple leaf parachute.

4-4 indicate apertures in leaves 1, 2 and 3, adapted to allow passage of air therethrough. I

5 5 indicate the usual rigging of a parachute, connecting the outer edges of leaves 1, 2 and 3, and supporting load 7.

66 indicate cords attached at points on the inner margins of the envelopes 1, 2 and 3 surrounding apertures 4-4, adapted to maintain the required relative position between said envelopes and to partially support load 7.

8 indicates a net adapted to cover apertures 4:4 and prevent the rigging of either leaf passing therethrough or becoming entangled therein.

Small arrows in Figure 3 indicate the direction of moving air beneath each of the several leaves to pass through its aperture 4.

In assembling my novel parachute I provide that cords 66 shall be slightly shorter than cords 55, in order that the first pull a of the load shall be on the approximate center of the envelope; this to prevent collapse of the envelope. It will be noted that in the ordinary type of parachute the envelope must open against the pull of the load on the outer edges of the same, while in my invention the operation of opening is quite the rethe air below, an

verse of the common type; namely, my parachute opens from center toward the periphgull on the envelope I acunder such conditions more surface is sub-i ject to air currents and drift results. By

, sulting when my parachute first opens will be maintaining an approximate horizontal plane forthe envelope and allowing a vent for the inrushing air from all sides, myform of parachute in great measure eliminates the objectionable features enumerated.

It will be apparent that the first shockre somewhat dissipated by the rapid rush of air through the aperture, (a shock absorber, as it were), but that the first rush of air will automatically lessen as the parachute assumes its normal rate of descent.

It is reasonable to suppose, further, that the up-rushing air through the vent will serve to create a partial vacuum above the envelope esired object of maintainof the United States upon the following claims 1. A parachute of the character disclosed comprising multiple leaves; each of sai leaves provided with an aperture approximate the center thereof; a net covering each of said apertures; means of maintaining said leaves in approximate horizontal plane and supporting a load, comprising multiple cords from said load to the outer and inner mar- 'ns of each of said'leaves, said cords to said mner margins being relatively shorter than said cords to said outer margim 2.:In a parachute of the character disclosed, multiple parachute leaves, the'upper one thereof being the largest, and each successive lower one of smaller diameter than itsv next above; an aperture at approximate the center of each of said leaves; a net covering each of said apertures; means of supporting a load comprising multiple cords attached to the outer and inner margins of each of said leaves, said leaves being s aced relative to said load and to each other in the form of an invertedcone; said cords to the inner margin of said leaves relatively shorter than said cords to said outer margin thereof, and adaptsurrounding the vent, thus augmenting the ed to maintain said leaves in approximate '80 lifting power.

In order that there may be as little danger of entangling rigging as possible, I have placed a net to cover each of the vents, both in single leaf and compounded parachutes.

In compounding the units of my invention I prefer to use three as illustrated, forming in general the linesof an inverted cone, the upper largest and each succeeding lower one horizontal plane; all substantially as set forth. i

3. Adevice of the character disclosed, comprising a plurality of spaced apart parachutes, each parachute including an envelope provided with a central opening, and load supporting cords attached to the outer and inner'margins of each envelope.

4. A device of the character disclosed, comprising a plurality of spaced apart para chutes, each parachute including an envelope provided with a central opening, and load supporting cords attached to the outer and inner margins of each envelope, each parachute being of different diameter.

In witness whereof I have set my hand to this petition, specification and power of at-. torney this 29th day of June, 1927.

OSWELL A. AKER. 

